Down Syndrome and Dementia: An Emerging Need for Better Support
By Healy ML FRACP1,2, Foster A PhD1, Brodtmann B FRACP PhD2,3, Payne D4, Steff D5, Ayton D (PhD, MPH, BiomedSci (Hons)2
1Monash Health
2Monash University
3Eastern Health
4Down Syndrome Victoria
5Down Syndrome Australia
People with Down syndrome are living longer than ever. With this welcome increase in life expectancy comes a growing need to recognise and respond to age-related health conditions, including Alzheimer’s disease.
There are an estimated 13,000 to 15,000 Australians with Down syndrome. Life expectancy has increased dramatically over the past 50 years, reaching a median of around 58 years from 2000 onwards. However, people with Down syndrome have a much higher risk of developing Alzheimer’s disease, often at a younger age. Around 95 per cent are estimated to develop early-onset Alzheimer’s disease, with a median age of diagnosis around 54.
This means dementia needs to be part of conversations about healthy ageing for people with Down syndrome much earlier in life.
Down Syndrome Australia, working together with the local State and Territory Down syndrome organisations have been increasing the information and supports available to people with Down syndrome, their families and professionals to better understand and navigate the challenges that come with ageing with Down syndrome.
Recognising the early signs
Families, carers and disability support workers have an important role to play in noticing changes in a person’s abilities and behaviour. Dementia does not necessarily look the same in everyone with Down syndrome. Earlier research placed particular emphasis on changes such as apathy and agitation, but more recent research has shown that memory loss can also be an early sign.
Changes might include increased forgetfulness, misplacing things or difficulty completing tasks that the person previously managed confidently. These changes can be difficult to identify, particularly when support workers change frequently and knowledge of a person’s usual abilities is lost between different carers.
Establishing a baseline of a person’s cognitive abilities earlier in life can make it easier to identify meaningful changes later. International guidelines recommend establishing a cognitive baseline from around age 30 and screening for dementia from around age 40.
Importantly, any noticeable change in memory or ability should be discussed with a GP.
Better pathways are needed
Despite the increased risk, Australia has limited specialist dementia services for people with Down syndrome. Standard dementia assessments may not be suitable for people with intellectual disability, while healthcare professionals may not have the specialist training needed to distinguish dementia from a person’s existing intellectual disability. This can lead to diagnostic overshadowing, where new symptoms are incorrectly attributed to the person’s Down syndrome.
A timely diagnosis can help families, support teams and the person understand what is happening and put appropriate supports in place. It can also help identify other conditions that may contribute to changes in cognition, such as sleep apnoea, depression or hearing and vision problems.
A more inclusive approach
Encouragingly, Australia is beginning to develop more specialised services.
In 2025, Monash Health launched Australia’s first Down syndrome Brain Health Service, designed with input from people with Down syndrome and their families. The service provides baseline cognitive assessment, specialist assessment and diagnosis, and ongoing support. Its approach goes beyond dementia testing to consider brain health more broadly, including physical activity, sleep and overall wellbeing.
The experience of the service highlights an important principle: people with Down syndrome should be directly involved in shaping the healthcare services designed for them.
As more people with Down syndrome live into older age, Australia needs dementia services, health professionals and disability support workers to be better prepared.
With greater awareness, earlier assessment, specialised support and better-trained care teams, people with Down syndrome can have the opportunity to receive the right support at the right time – helping them and their families navigate ageing with greater confidence and independence.
You can find out more about the intersection of Down syndrome and dementia by subscribing to the Australian Journal of Dementia Care.